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Helicobacter pylori (H. pylori) is a main risk factor for gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is involved in the development and progression of H. pylori-associated GC. However, the exact molecular mechanism of this process remains unclear. The AKT/GSK3β signaling pathway has been demonstrated to promote EMT in several types of cancer. The present study investigated whether H. pylori infection induced EMT, and promoted the development and metastasis of cancer in the normal gastric mucosa, and whether this process was dependent on AKT activation. The expression levels of the EMT-associated proteins, including E-cadherin and N-cadherin, were determined in 165 gastric mucosal samples of different disease stages by immunohistochemical analysis. The expression levels of E-cadherin, N-cadherin, AKT, phosphorylated (p-)AKT (Ser473), GSK3β and p-GSK3β (Ser9) were further determined in H. pylori-infected Mongolian gerbil gastric tissues and cells co-cultured with H. pylori by immunohistochemical analysis and western blotting. The results indicated that the expression levels of the epithelial marker E-cadherin were decreased, whereas the expression levels of the mesenchymal marker N-cadherin were increased during gastric carcinogenesis. Their expression levels were associated with H. pylori infection. Furthermore, H. pylori infection resulted in downregulation of E-cadherin expression and upregulation of N-cadherin expression in Mongolian gerbils and GES-1 cells. In addition, an investigation of the associated mechanism of action revealed that p-AKT (Ser473) and p-GSK3β (Ser9) were activated in GES-1 cells following co-culture with H. pylori. Furthermore, following pretreatment of the cells with the AKT inhibitor VIII, the expression levels of E-cadherin, N-cadherin, p-AKT and p-GSK3β did not show significant differences between GES-1 cells that were co-cultured with or without H. pylori. The levels of p-AKT and p-GSK3β were increased in H. pylori-infected Mongolian gerbils. In conclusion, the present study demonstrated that H. pylori infection activated AKT and resulted in the phosphorylation and inactivation of GSK3β, which in turn promoted early stage EMT. These effects were AKT-dependent. This mechanism may serve as a prerequisite for GC development.  相似文献   
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The developing CNS is exposed to physiological hypoxia, under which hypoxia-inducible factor α (HIFα) is stabilized and plays a crucial role in regulating neural development. The cellular and molecular mechanisms of HIFα in developmental myelination remain incompletely understood. A previous concept proposes that HIFα regulates CNS developmental myelination by activating the autocrine Wnt/β-catenin signaling in oligodendrocyte progenitor cells (OPCs). Here, by analyzing a battery of genetic mice of both sexes, we presented in vivo evidence supporting an alternative understanding of oligodendroglial HIFα-regulated developmental myelination. At the cellular level, we found that HIFα was required for developmental myelination by transiently controlling upstream OPC differentiation but not downstream oligodendrocyte maturation and that HIFα dysregulation in OPCs but not oligodendrocytes disturbed normal developmental myelination. We demonstrated that HIFα played a minor, if any, role in regulating canonical Wnt signaling in the oligodendroglial lineage or in the CNS. At the molecular level, blocking autocrine Wnt signaling did not affect HIFα-regulated OPC differentiation and myelination. We further identified HIFα–Sox9 regulatory axis as an underlying molecular mechanism in HIFα-regulated OPC differentiation. Our findings support a concept shift in our mechanistic understanding of HIFα-regulated CNS myelination from the previous Wnt-dependent view to a Wnt-independent one and unveil a previously unappreciated HIFα–Sox9 pathway in regulating OPC differentiation.SIGNIFICANCE STATEMENT Promoting disturbed developmental myelination is a promising option in treating diffuse white matter injury, previously called periventricular leukomalacia, a major form of brain injury affecting premature infants. In the developing CNS, hypoxia-inducible factor α (HIFα) is a key regulator that adapts neural cells to physiological and pathologic hypoxic cues. The role and mechanism of HIFα in oligodendroglial myelination, which is severely disturbed in preterm infants affected with diffuse white matter injury, is incompletely understood. Our findings presented here represent a concept shift in our mechanistic understanding of HIFα-regulated developmental myelination and suggest the potential of intervening with an oligodendroglial HIFα-mediated signaling pathway to mitigate disturbed myelination in premature white matter injury.  相似文献   
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随着对肿瘤热疗和肿瘤免疫微环境(TIME)的深入研究,近年来热疗对TIME的作用越来越受到学者们的重视。本文就目前国内外研究进展,对热疗与TIME中几类主要免疫细胞和免疫相关细胞因子的影响及作用机制作一综述。全面而透彻的了解热疗对TIME的调控作用,有助于为肿瘤治疗提供新的思路和方法。  相似文献   
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目的:统计分析中国县级及以上医疗机构青光眼亚专科建设、诊疗设备配备和服务提供情况,为进 一步推动我国青光眼防治工作提供理论依据。方法:调查研究。2015年对全国提供眼科服务的县级 及以上医疗机构通过网上填报的方式进行普查,采用描述性统计方法,对我国县级及以上医疗机构 青光眼亚专科建设、诊疗设备配备和服务提供情况进行系统整理和统计分析。结果:本次调查覆盖 全国6 341家县级及以上医疗机构,其中设立青光眼亚专科的医疗机构有672家(10.60%)。在青光眼 检查和治疗相关设备中,视力表配置率最高(99.30%),平均每家医疗机构配置3.28台;超声生物显 微镜配置率最低(11.50%),平均每家医疗机构配置0.13台。眼压测量、白内障手术和小梁切开术是 青光眼主要的诊疗服务类型。结论:我国县级及以上医疗机构青光眼亚专科建设亟待加强,诊疗设 备配备不全,诊疗服务能力需要全面提升。  相似文献   
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Algorithms based on deep neural networks (DNNs) have attracted increasing attention from the scientific computing community. DNN based algorithms are easy to implement, natural for nonlinear problems, and have shown great potential to overcome the curse of dimensionality. In this work, we utilize the multi-scale DNN-based algorithm (MscaleDNN) proposed by Liu, Cai and Xu (2020) to solve multi-scale elliptic problems with possible nonlinearity, for example, the p-Laplacian problem. We improve the MscaleDNN algorithm by a smooth and localized activation function. Several numerical examples of multi-scale elliptic problems with separable or non-separable scales in low-dimensional and high-dimensional Euclidean spaces are used to demonstrate the effectiveness and accuracy of the MscaleDNN numerical scheme.  相似文献   
39.
陈梅  付丛会  沈志强  徐英  贾杰  吴毅 《临床荟萃》2020,35(4):357-361
目的 观察互动式歌唱表演对轻中度阿尔茨海默病(AD)患者抑郁、精神行为症状及运动训练参与率的影响。方法 选取符合入组条件≥60周岁AD患者63例,随机分为研究组(31例)和对照组(32例)。所有受试患者常规药物治疗及常规运动训练,对照组接受被动性音乐治疗,研究组接受以互动歌唱为主的主动性音乐治疗,1次/d,每次1小时,每周训练5天,持续干预6个月。于治疗前、治疗1个月后、治疗3个月后、治疗6个月后分别采用康奈尔痴呆抑郁量表(CSDD)评分、阿尔茨海默病病理行为(BEHAVE AD)评分、参与率进行评估。结果 治疗1个月、3个月后,研究组CSDD评分较治疗前均降低(P<0.05);治疗6个月后,研究组患者CSDD评分较治疗前、治疗1个月、3个月后均显著降低(P<0.05),且与对照组比较差异有统计学意义(P<0.05)。治疗1个月、3个月后,研究组BEHAVE AD评分较治疗前均降低(P<0.05);治疗6个月后,研究组患者BEHAVE AD评分较治疗前、治疗1个月、3个月后均显著降低(P<0.05),且与对照组比较差异有统计学意义(P<0.05)。治疗6个月后,两组运动训练参与率组间比较差异有统计学意义(P<0.05)。结论 互动式歌唱表演可能对改善轻中度AD患者的抑郁和精神行为症状有着积极的疗效,同时对提高受试者运动训练的参与率可能有着更积极的疗效。  相似文献   
40.
[目的]观察评价可吸收明胶海绵棒在椎弓根置钉过程中的止血效果。[方法]2017年10月~2018年6月,48例胸腰椎骨折即将行后路手术的患者纳入本研究,采用随机数字表法分为明胶海绵组和骨蜡组。明胶海绵组共23例,置钉过程中应用明胶海绵棒填塞至椎弓根孔道止血;骨蜡组共25例,在透视定位时应用骨蜡封闭椎弓根孔道。记录置钉情况;记录术中出血量、自体血回输量、置钉过程中的出血量、输血量;检测术前和术后5 d RBC、HB和HCT。[结果]两组在置钉总数、伤椎置钉数、伤椎位置各椎置钉数量的差异均无统计学意义(P>0.05)。术后两组各出现1例小腿肌间静脉血栓,抗凝治疗后于复查时消失。术后两组均无明胶海绵或骨蜡导致的不良反应。两组在术中出血量、术中自体血回收量、输血量的差异无统计学意义(P>0.05),但明胶海绵组上述指标均小于骨蜡组。每钉置入过程中明胶海绵组的出血量显著少于骨蜡组,差异有统计学意义(P<0.05)。两组术后5 d的RBC、HB和HCT均较术前显著减少,两时间点间差异均有统计学意义(P<0.05)。术前两组在RBC、HB和HCT的差异均无统计学意义(P>0.05),术后5 d两组在RBC、HB和HCT的差异亦均无统计学意义(P>0.05)。[结论]应用明胶海绵棒填塞椎弓根孔道止血可显著减少安置椎弓根螺钉过程中的出血,是一种简单、安全、有效的脊柱外科术中止血方法。  相似文献   
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